EventEarlyNotification timestamp bugfix and other changes (#84)

This PR fixes EventEarlyNotification timestamp not displaying correctly
and also has some other changes:
- Add xmldocs for `/settingslist`'s `page` option in
SettingsCommandGroup.cs
- Add option description for `index` for `/delreminder`
- Some corrections of grammatical errors in Messages.tt-ru.resx
- Fix `ArgumentOutOfRangeException` in `/settingslist` that appears if
the user uses a negative integer in `page`

---------

Signed-off-by: Macintosh II <95250141+mctaylors@users.noreply.github.com>
Co-authored-by: Octol1ttle <l1ttleofficial@outlook.com>

locale/Messages.tt-ru.resx

@@ -253,11 +253,11 @@
     <value>оъмъомоъемъъео((((</value>
   </data>
     <data name="EventCancelled" xml:space="preserve">
-    <value>движуха "{0}" отменен!</value>
-  </data>
+        <value>движуха "{0}" отменена!</value>
+    </data>
     <data name="EventCompleted" xml:space="preserve">
-    <value>движуха "{0}" завершен!</value>
-  </data>
+        <value>движуха "{0}" завершена!</value>
+    </data>
     <data name="Ever" xml:space="preserve">
     <value>всегда</value>
   </data>